Öz
This paper presents two practical computational procedures
to predict the steering and braking forces applied by tractor type escort tugs
to large vessels, particularly oil tankers. The essential part of the escort
performance prediction methodology is the computation of hydrodynamic forces
generated by the tug’s hull and the appendages such as skeg. These forces can
be converted into the steering and braking force components which define the
escort performance of the tug. The hydrodynamic forces can be estimated by
scaled model tests however this approach is not suitable for early design
studies because of cost and time restrictions. The first methodology presented
in this paper is based on semi-empirical methods, obtained from model test
measurements and full-scale test results, and developed in order to be used at
early design stages where limited design information is available. A
computational technique based on Reynolds-Averaged-Navier-Stokes (RANS)
equations is recommended for the later stages of design process in which more
precise definition of hull and appendages geometries are available. This
approach, which takes local flow characteristics into account, can be used for
the optimisation of hull and appendages geometries. In this study, two different
approaches are presented and used on a given escort tug.
Anahtar Kelimeler
Kaynakça
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Ayrıntılar
| Birincil Dil | Türkçe |
|---|---|
| Konular | Mühendislik |
| Bölüm | Makaleler |
| Yazarlar | |
| Yayımlanma Tarihi | 15 Aralık 2017 |
| Yayımlandığı Sayı | Yıl 2017 Sayı: 210 |
- Makale Dosyaları